Project 1 is a longitudinal cohort study of 425 HIV-positive persons to determine the minimal effects of nutritional status on the outcome of HIV infection. The cohort is stratified by CD4 counts into <200 cells/mm/3 (28%), 200-499 cells/mm/3 (47%), and a greater than or equal to 500 cells/mm/3 (25%) and is comprised of 38% minorities and 27% women. Efforts will be directed at maintaining this important Nutrition for Life (NFL) cohort and completing the data collection and analysis from the initial study. New hypotheses will be addressed that reflect the changing nature of the HIV epidemic: concordant and discordant nutritional responses to highly active anti-retroviral therapy (HAART); the effect of increasing obesity on the outcome of HIV disease; the role of testosterone deficiency in determining body composition and physical functioning; the nutritional effect of SI virus in the small intestine; the role of micronutrients in determining response to HAART; and the effect of concurrent chronic viral hepatitis on clinical status, outcome, and HIV infection. Project 1 will measure weight and body composition, dietary intake, metabolic and hormonal parameters, serum micronutrient levels, gastrointestinal and liver function, and lipid profiles every six months in this cohort. Outcome measures include: body composition analysis, particularly lean body mass assessment of HIV infection by viral load, CD4 counts, opportunistic infections, and death; assessment of physical functioning by questionnaires, hand grip, and six-minute walk; health-related quality of life by questionnaire; and occurrence of diabetic and cardiovascular complications. Nutritional status has been a strong predictor of outcome from HIV infection and influences physical function and clinical status. Despite the advent of HAART, wasting continues to contribute to morbidity and mortality from HIV infection. In addition, some persons with HIV do not respond to HAART virologically or have a discordant virologic and nutritional response. Nutritional complications of HAART include fat redistribut8ion (lipodystrophy) and hyperlipidemia. By determining the continued role of nutrition in HIV infection, targeted interventions can be made to improve outcome and survival, and to reduce complications of HIV infection and treatment.